Add TPC-DS SLT tests with plans and Parquet parity

[joseph-isaacs]

Summary

Follow-up to #9794 (ClickBench): the same SLT layout for TPC-DS at scale factor 0.1. Stacked on the DuckDB/Vortex scan fixes PR, without which the DuckDB suite returns wrong results for q9 and q28 and stalls partway through the 99 queries.

Changes

• slt/tpcds/generate_data.sh generates the 24 tables with DuckDB's tpcds extension through uvx, exports them to Parquet, converts each to Vortex with vx convert, and then runs duckdb/parity.slt, which reads every table in both formats through DuckDB and fails if any row differs. slt/generate_data.sh accepts tpcds like the other datasets; CI already calls the wrapper.
• Per engine: create.slt.no, drop.slt.no, results/q1..q99.slt.no and plans/q1..q99.slt.no from the upstream queries in vortex-bench/sql/tpcds, run unchanged. tpcds.slt asserts results and EXPLAIN plans (EXPLAIN (FORMAT json) with explain_output = 'all' on DuckDB) against Vortex; parquet.slt reruns the same result records against Parquet so both formats must agree. All 99 queries run on both engines with no errors, and no tie-breaking edits to the queries were needed.
• The runner registers TPC-DS as a generated-data suite, so its tests are ignored until both fixture formats exist. README updated.

Fixture size: 14MB, of which 12MB is the DuckDB JSON plans (the format the TPC-H PR chose).

Checks run: cargo nextest run -p vortex-sqllogictest -E 'test(tpcds)' twice (5 passed each), full cargo nextest run -p vortex-sqllogictest (144 passed), clippy on vortex-sqllogictest.

🤖 Generated with Claude Code

https://claude.ai/code/session_01L57FHoJ15heJVNaqgRq7xB

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Generated by Claude Code

[codspeed-hq]

Merging this PR will degrade performance by 3.38%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
❌ 1 regressed benchmark
✅ 2197 untouched benchmarks
⏩ 206 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	decompress[u64, (4000, 1024)]	70.5 µs	85.7 µs	-17.71%
⚡	Simulation	allocate_drop_arrow[0]	456.9 ns	402.7 ns	+13.45%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing claude/tpcds-slt-plans (9e66771) with claude/duckdb-vortex-scan-fixes (06fa41d)²}

Footnotes

1. 206 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

2. No successful run was found on claude/duckdb-vortex-scan-fixes (385e8ec) during the generation of this report, so f7f6b87 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[joseph-isaacs]

CI status on the previous head (a8ed1a2):

• SQL logic tests failed on the TPC-H DuckDB plan for q11: with Vortex scans no longer merged by DuckDB's common-subplan optimizer (the fix in Fix DuckDB scans over Vortex being merged or stalling #9803), q11's scalar subquery is not folded into a shared CTE any more, so its expected plan changed. Regenerated in Fix DuckDB scans over Vortex being merged or stalling #9803 (385e8ec); this PR is rebased on it (9e66771). Results are unchanged.
• Rust tests (coverage) (tests) failed only because vortex-btrblocks::schemes::integer::tests::compress_large_int hit the 150s nextest timeout under coverage instrumentation. Neither PR touches vortex-btrblocks or anything it depends on, and the same job with the same code on Fix DuckDB scans over Vortex being merged or stalling #9803 (06fa41d) passed its test step. Both jobs re-run on the new heads.

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Generated by Claude Code